(a) Field of the Invention
The present invention is related to a fuel cell system having a hydrogen supply manifold that securely supplies a stack with fuel gas and moisture, the stack generates uses the fuel gas and moisture to generate electrical energy, wherein a pressure of hydrogen is decreased to be recirculated and the compact packaging of the recirculation structure is realized.
(b) Description of the Related Art
As known in the related art, a fuel cell vehicle having a fuel cell system supplies a fuel cell stack with hydrogen as fuel so as to generate electricity, and the electricity that is generated by the fuel cell stack operates a motor so as to move a vehicle.
Herein, a fuel cell system does not transform chemical energy of fuel to combustion heat and is a electricity generation system that transforms chemical energy of fuel to electrical energy through electrochemical process.
The fuel cell system supplies a fuel electrode (anode) of a fuel cell with high purity of hydrogen from a hydrogen storage tank and uses an air supply device such as an air blower to supply an air electrode (cathode) of a fuel cell with atmosphere air.
Thus, the hydrogen that is supplied to a fuel cell stack is divided into a proton and an electron, the divided hydrogen ion is supplied to an air electrode (cathode) through a high molecule electrolyte film, oxygen that is supplied to an air electrode combines with an electron that comes in an air electrode to form moisture, and then the electrical energy is generated therein.
Generally, a fuel cell vehicle uses electricity that is generated by reacting hydrogen and oxygen in a stack so as to operate a motor such that a vehicle can be moved. For this purpose, it is necessary to supply a stack with a predetermined pressure of hydrogen.
Also, it is necessary to large amount of hydrogen so as to increase a flying distance of a fuel cell vehicle, and therefore a fuel cell vehicle uses a high pressure hydrogen tank having hundreds of pressure in a fuel cell vehicle.
Accordingly, a plurality of valves and regulators are disposed to decrease pressure of hydrogen between a hydrogen tank and a stack, and a plurality of pipes and manifolds are used to connect them respectively.
However, the more the portions connecting parts, the higher the possibility of hydrogen leak, and also O ring and sealing members are necessary so as to keep air-tightness, the cost is increased, and the productivity is deteriorated.
Also, because points that is to be measure a leak after the manufacturing and maintenance of the system is increased, air-tightness test time and cost are increased. In addition, when a fitting and tubing is used to configure a gas supply line, connecting portions are increased, and it is hard to use an automatic device to assemble them and to manage an assembly torque. Accordingly, fuel cell vehicle has been making makes an effort to decrease connecting portions/volume of a hydrogen supply system (fuel processing system) having a valve and a regulator.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.